Files
sx/library/modules/math/vector2.sx
agra bdd0e96d78 feat(lang): block value requires no trailing ; (Rust-style)
A block's value is now its last statement ONLY when that statement is a
trailing expression with no `;`. A trailing `;` discards the value,
leaving the block void. This makes value-vs-statement explicit and lets
the compiler reject "this block was supposed to produce a value".

Compiler:
- Parser records `Block.produces_value` (last stmt is a no-`;` trailing
  expression) + `Block.discarded_semi` (the `;` that discarded a value),
  via `expectSemicolonAfter`. A trailing expression before `}` may now
  omit its `;` (previously a parse error). Match-arm and else-arm bodies
  are built value-producing regardless of the arm `;` (arms are exempt —
  the `;` is an arm terminator).
- Lowering: `lowerBlockValue` / the block-expr path / `inferExprType`
  respect `produces_value`. A value-position block that discards its value
  is a hard error (`lowerValueBody` for function bodies; the value-context
  `.block` path for if/else branches, `catch` bodies, value bindings,
  match arms). Pure-failable `-> !` bodies (value rides the error channel)
  and a value-if whose branches are void are handled without false errors.
- `defer`/`onfail` cleanup bodies lower as statements (void), so a
  trailing `;` there is fine.

Migration (behavior-preserving — output unchanged):
- stdlib + ~210 examples: dropped the trailing `;` on value-position last
  expressions. `format` now ends with an explicit `#insert "return
  result;"` (it relied on `#insert`-as-block-value, which `;` discards).
- Two `main :: () -> s32` examples that relied on the old silent
  default-return got an explicit trailing `0`.
- Rejection snapshots 0412 / 1013 regenerated (their quoted source lines
  lost a `;`); the diagnostics themselves are unchanged.

Docs/tests: specs.md "Block values" section; examples 0040 (rules) + 0041
(rejection); 3 parser unit tests. Filed issue 0066 (pre-existing
match-arm negated-literal phi-width quirk, surfaced not caused here).

Gates: zig build, zig build test, run_examples.sh -> 343 passed,
cross_compile.sh -> 7 passed (also refreshed its stale example names).
2026-06-02 09:23:50 +03:00

50 lines
1.1 KiB
Plaintext

Vec2 :: struct {
x, y: f32;
zero :: () -> Vec2 { Vec2.{ x = 0.0, y = 0.0 } }
add :: (self: Vec2, b: Vec2) -> Vec2 {
Vec2.{ x = self.x + b.x, y = self.y + b.y }
}
sub :: (self: Vec2, b: Vec2) -> Vec2 {
Vec2.{ x = self.x - b.x, y = self.y - b.y }
}
scale :: (self: Vec2, s: f32) -> Vec2 {
Vec2.{ x = self.x * s, y = self.y * s }
}
dot :: (self: Vec2, b: Vec2) -> f32 {
self.x * b.x + self.y * b.y
}
length :: (self: Vec2) -> f32 {
sqrt(self.x * self.x + self.y * self.y)
}
normalize :: (self: Vec2) -> Vec2 {
len := self.length();
if len > 0.0 {
return Vec2.{ x = self.x / len, y = self.y / len };
}
Vec2.zero()
}
lerp :: (self: Vec2, b: Vec2, t: f32) -> Vec2 {
Vec2.{ x = self.x + (b.x - self.x) * t, y = self.y + (b.y - self.y) * t }
}
distance :: (self: Vec2, b: Vec2) -> f32 {
self.sub(b).length()
}
negate :: (self: Vec2) -> Vec2 {
Vec2.{ x = 0.0 - self.x, y = 0.0 - self.y }
}
equals :: (self: Vec2, b: Vec2) -> bool {
self.x == b.x and self.y == b.y
}
}